Nearly every time you stumble upon an error opening a workbook that you created by code, the reason is some not properly closed resource. Unfortunately, I experienced that a lot of times ;-)
In my cases, I could resolve the issue by the following sequence of actions (order matters):
- write the workbook:
workbook.write(out);
- force the
FileOutputStream to empty all used buffers: out.flush();
- close the
FileOutputStream: out.close();
- close the workbook:
workbook.close();
This is how I would add the missing actions to your code:
try {
Workbook workbook;
workbook = new XSSFWorkbook(OPCPackage.open(GlobalVariables.XLSM));
Sheet sheet = workbook.getSheetAt(0);
Row row = sheet.createRow(recordcount + 5);
Cell cell;
cell = row.createCell(GlobalVariables.testID);
cell.setCellValue(recordcount);
FileOutputStream out = new FileOutputStream(new File(File));
// 1. write the workbook
workbook.write(out);
// 2. force the FileOutputStream to write everything out before closing it
out.flush();
// 3. then close the FileOutputStream
out.close();
// 4. finally close the workbook
workbook.close();
System.out.println("Data was written in XLSM");
} catch (FileNotFoundException e) {
e.printStackTrace();
} catch (InvalidFormatException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
Please note that flushing the FileOutputStream might not always be necessary, but it was mentioned in several best-practice tutorials concerning apache-poi, so I decided to use it my code.
This works for me, I hope it will do so for you as well.
EDIT (OP asked for my example code in a comment below)
This is an independent example for reading and extending an XSSFWorkbook. It is all just in the main method, but at least commented ;-)
You have to change the path to the workbook, which is basically a String in this example and becomes a java.nio.Path afterwards.
public class PoiMain {
public static void main(String[] args) {
/*
* Setup:
* An existing xlsx file with a first sheet containing 6 columns and 1 row.
* The row has 6 filled cells with the values
* cell 1 (index 0): There
* cell 2 (index 1): is
* cell 3 (index 2): a
* cell 4 (index 3): house
* cell 5 (index 4): in
* cell 6 (index 5): New Orleans
*
* Task:
* Write the words "they", "call", "it", "the", "rising", "sun"
* in the cells below.
*/
// define the (correct) path to the workbook
String pathToFile = "Y:\\our\\path\\to\\the\\Test-Workbook.xlsx"; // you can use an xlsm here, too
// create a Path object
Path filePath = Paths.get(pathToFile);
// declare a workbook
XSSFWorkbook workbook;
try {
/*
* READING from the .xlsx file:
*/
FileInputStream in = new FileInputStream(filePath.toFile());
workbook = XSSFWorkbookFactory.createWorkbook(in);
XSSFSheet sheet = workbook.getSheetAt(0);
// read all the cells of the first row and print their content
for (int i = 0; i < sheet.getPhysicalNumberOfRows(); i++) {
XSSFRow row = sheet.getRow(i);
for (int j = 0; j < row.getPhysicalNumberOfCells(); j++) {
XSSFCell cell = row.getCell(j);
System.out.println(cell.getStringCellValue());
}
}
/*
* WRITING to the .xlsx file already read
*/
// create some meaningful words to be added to some cells in the workbook
List<String> wordsToBeWritten = Arrays.asList("they", "call", "it", "the", "rising", "sun");
FileOutputStream out = new FileOutputStream(filePath.toAbsolutePath().toString());
sheet = workbook.getSheetAt(0);
XSSFRow row = sheet.createRow(sheet.getPhysicalNumberOfRows());
// create new cells and write the words into them
for (int i = 0; i < wordsToBeWritten.size(); i++) {
XSSFCell cell = row.createCell(i);
cell.setCellValue(wordsToBeWritten.get(i));
}
// close the FileInputStream
in.close();
// write the workbook using the FileOutputStream
workbook.write(out);
// force the FileOutputStream to write everything until it is empty
out.flush();
// close the FileOutputStream
out.close();
// close the workbook.
workbook.close();
} catch (FileNotFoundException e) {
System.err.println(
"The file \"" + filePath.toAbsolutePath().toString() + "\" could not be found.");
e.printStackTrace();
} catch (IOException e) {
System.err.println("Error while reading the file \"" + filePath.toAbsolutePath().toString() + "\"");
e.printStackTrace();
} catch (InvalidFormatException e) {
System.out.println(
"The file \"" + filePath.toAbsolutePath().toString() + "\" has an invalid format(ting)");
e.printStackTrace();
} catch (EmptyFileException e) {
System.err.println("The supplied file \"" + filePath.toAbsolutePath().toString() + "\" is empty.");
e.printStackTrace();
}
}
